FIG. 3.

The IL-8 inducers in NTHI SCF are small and sensitive to peptidase and lipase. NTHI SCF was fractionated with a Centriplus (Millipore) fractionator with different pore sizes according to the manufacturer's instructions. Fractions were tested on IL-8-Luc-transfected epithelial cells for luciferase activity. IL-8-inducing activity in the fraction of >50 kDa is significantly different from that in other fractions (*, P ≤ 0.001). Data are presented as means ± standard deviations of three individual treatments. Results are representative of two separate experiments.